QAELUM Oracle Intelligence builds verified commodity data for markets that lack it: cocoa and cashew in Ghana, tuna in the Maldives, with Nigeria next. Our field agents stand at buying centres and landing sites with mid-range Android phones and record what was traded, at what price, where and when. Lenders, buyers and regulators then rely on that record, so every capture has to prove it came from a real phone, in a real place, at a real time, and wasn't changed afterwards.We already have a detailed written specification for the app, along with test vectors and a backend that verifies the app's output. We need the engineer who builds it.What you'll build:- A native Kotlin capture app for Android 13 and later, used by field agents in low-connectivity areas.- Hardware-backed device keys in the Android Keystore (ECDSA P-256, non-exportable, StrongBox where available), with key attestation and enrolment.- A deterministic encoder that matches our canonical format byte for byte, checked against published test vectors.- Signed capture statements covering the photo, its EXIF data, GPS and motion sensors, with privacy-sensitive data hashed on the device and never uploaded raw.- Offline capture sessions with an encrypted on-device queue that syncs when connectivity returns, and with a strict order in which a capture is committed before it can be submitted.- A device capability check at onboarding, so an agent knows on day one whether their phone qualifies.- Play Store compliance for sensitive permissions (camera, location, microphone).What we're looking for:- 5+ years of professional Android development, mostly in Kotlin, with apps shipped to production.- Hands-on experience with Android Keystore, key attestation and Play Integrity, or the clear ability to get there quickly.- Comfort with applied cryptography in practice: signatures, hashing, DER encoding, and byte-exact serialisation.- Experience with offline-first design, background work and encrypted local storage.- A habit of testing against specifications and vectors rather than "it works on my phone".- Clear written English. Our design work happens in documents and pull request reviews.Nice to have:- iOS experience (App Attest). iOS is a later, separate verification path.- Experience building for low-end devices and patchy networks in West Africa or South Asia.- Background in blockchain, Bittensor, fintech or supply-chain traceability.- Experience with CameraX and sensor APIs.How we work: Remote, async, documentation first. You'll work directly with the CTO and founders. Specifications are written down, decisions are recorded, and code is reviewed carefully.Include your CV, links to apps you've shipped or code you're proud of, and a few sentences on how you'd stop a captured photo being swapped after it was taken.
Not specified in the original listing.
Not specified in the original listing.
